My personal favorites for taste and quality are Le Maitre Chocolatier, corner Sherbrooke & Guy and Gendron. Gendron does not have a shop, but you may contact them directly at 450-646-6001. You may also want to check out their facebook page:

I haven't tried enough different chocolates there to get really specific with recommendations, but everything I've had has been good, including truffles (I forget what specific kinds I had), butter pecan fudge and 64% bittersweet baking chocolate.